Is This The Most Important Hormone In The Female Body?

Estrogen, oh estrogen. Where would we be without you? As women, estrogen is hugely important. Primarily produced in the ovaries, though a small amount is also produced in the adrenal glands, estrogen acts just about everywhere in the body — affecting everything from mood regulation, to sleep promotion, energy levels, memory, and of course reproductive function. We’ve been known to say “hormones are everything”… and we mean it. They definitely have a big impact on how you feel, mentally and physically.

In truth, we wouldn’t get very far without all of the hormones that are key to our proper functioning, which include progesterone, serotonin, testosterone, oxytocin, insulin, melatonin, thyroid hormones… and many more. For a full list, check out this simple chart.

All of our hormones work together and, in ideal conditions, operate in a delicate balance to keep our systems regulated and running smoothly. When any one of those hormones gets out of balance, we’ll really start to feel it. And that’s why, as a woman, it’s so important that you know about estrogen — because when your estrogen levels are too high or too low, it can have reverberating impacts on your overall health and wellness.

Like all of the female reproductive hormones, estrogen is constantly rising and falling in line with your cycles, so it’s natural for it to fluctuate. But other factors in our life, such as age, stress, and environmental toxins can disrupt estrogen levels further. Today, we’re going to go over what you need to know about estrogen, what types of estrogen are dominant at various stages of your stage of life, how estrogen impacts you in pregnancy and postpartum, and how it changes in your 40s.

What are the various types of estrogen?

But as we age and change, estrogen changes with us, which is why there are several types of estrogen to know about:

Estradiol (E2):

This is the most common kind of estrogen (and the one you hear about most often). It’s largely present in a woman’s reproductive years — between puberty and menopause.

Estriol (E3):

This form of estrogen is key for our Baby2Body audience! It takes priority during pregnancy as it’s released from the placenta. It’s responsible for creating a healthy uterine environment for your baby to grow in and readies the female body for childbirth.

Estrone (E1):

This form of estrogen takes over in the post-menopausal years and is a weaker form of estrogen.

How does estrogen work in the female body?

Estrogen is the prototypical “female” hormone, as it directs all of the things that create a biologically female body: the growth of breast tissue, the maintenance of healthy vaginal tissue, the start of menstrual cycles, and the ability to grow and nurture a fetus in the womb. But estrogen has many more impacts throughout the body.

It plays a crucial role in maintaining a healthy heart and blood vessels and regulating cholesterol. Estrogen also prevents bone mass loss, and as levels drop your risk of osteoporosis can increase. It supports healthy skin, hair, and collagen production, and is believed to have anti-aging effects. Lastly, this critical hormone also impacts brain health — impacting everything from body temperature regulation to memory function, libido, and moods.

What happens when estrogen is too high?

When it comes to hormones — it’s all about balance. When one hormone is too high, or too low, it can lead to uncomfortable and unhealthy symptoms that are important to be aware of. High estrogen can be caused by things like hormonal contraceptives, hormone replacement therapy, certain medications, and even some herbal remedies are thought to increase estrogen levels.

These are the most common symptoms of high estrogen in women:

• Weight gain and bloating, especially around the midsection

• Irregular periods and heavy bleeding

• More severe PMS

• Difficulty sleeping

• Fatigue

• Hair loss

• Headaches

• Low libido

• Swollen or tender breasts

• Uterine fibroids and endometriosis

What happens when estrogen is too low?

Low estrogen levels can be caused by certain medical conditions, thyroid disorders, excessive exercise, and eating disorders that severely reduce body fat.

Low estrogen also comes with its own host of unpleasant symptoms:

• Vaginal dryness and pain during intercourse

• Irregular or absent periods, and resulting infertility

• Severe mood swings

• Depression

• Hot flashes

• Migraines

• Difficulty concentrating

• Fatigue

Being aware of symptoms related to hormonal imbalances — especially estrogen imbalances — is so important in helping you better understand your health as a woman.

Now, let’s look at how estrogen is supposed to function at different stages of your life…

What does estrogen do during your menstrual cycle?

There are four hormones that dictate your menstrual cycle:

1. Estrogen

2. Progesterone

3. Follicle-stimulating hormone (FSH)

4. Luteinizing hormone (LH)

Estrogen’s role in the menstrual cycle is to prepare your body for a possible pregnancy. In the first few days of your cycle (when you’re on your period) estrogen levels are relatively low. The first spike of estrogen comes around the midpoint of your cycle (about 14-16 days before your next period), and that increase is what triggers a spike in FSH and LH. The increase in these two hormones is what leads to ovulation, or the release of a mature egg.

After ovulation, estrogen remains high, which helps thicken the lining of the uterus and prepare the body for the possible implantation of a fertilized egg. We’ll say it again: estrogen’s main objective is to get you pregnant, and if you don’t conceive, it will drop pretty quickly. This sudden drop in estrogen can lead to a drop in serotonin, and that combination is what is thought to contribute to PMS. (Thanks estrogen, we get the hint…).

What does estrogen do during pregnancy?

Whenever you do conceive, estrogen will be ready to party.

Estrogen in your first trimester: estrogen levels go through their most significant increase as the placenta will start producing E3 as well. This rapid incline is thought to contribute to many of the first trimester symptoms: fatigue, increased appetite, skin changes, mood swings, and may also contribute to nausea (though that is thought to be more closely linked to the hormone hCG).

Estrogen in your second & third trimester: Estrogen levels will continue to slowly increase through the rest of pregnancy, and its main function is to maintain the healthy growth of the uterus and promote your baby’s development by supporting blood flow and the transfer of nutrients. Estrogen is also acting on mammary glands in the second and third trimesters, preparing you for lactation while preventing too much milk production at this time.

What happens to estrogen after birth?

Childbirth is an incredible feat of the female body. To prepare you for that, you’ll likely experience a surge of estrogen and progesterone right before birth, but those quickly drop after delivery. In fact, it’s believed that those hormones reach nearly pre-pregnancy levels in the first 24 hours after birth. Since high levels of estrogen and progesterone can inhibit milk production, this decline is supposed to happen. The hormone responsible for social connection and bonding — oxytocin — rises to compensate for this decline and help you connect with your baby.

However, the sudden drop in estrogen and progesterone can leave women feeling a bit off after childbirth, and the decrease in estrogen is thought to contribute to many postbirth symptoms, including:

• The baby blues. Your hormones should regulate soon after birth and feelings of baby blues should subside, however, if they don’t it’s important to keep an eye out for further signs of postpartum depression.

• Vaginal dryness

• Night sweats

• Hair loss

Find out more about the Postpartum Hormone Crash here!

How does estrogen change in your 40s?

Around the age of 40, many women start to experience fluctuations in estrogen, with hormone levels gradually declining overall. It won’t feel like a sudden change, but more like small things that just start to feel different. You might:

• Have more trouble sleeping through the night

• Have more joint pain than you remember

• Feel sorer after your regular workouts

• Bbe a bit more irritable than you’re used to

• Find that you have a bit more trouble concentrating and remembering your train of thought.

These are all signs of dropping estrogen and the start of what’s called perimenopause.

What is perimenopause?

When your estrogen starts dropping it’s technically considered the perimenopause period. We know this can come as a shock, as menopause itself might be 10-15 years away for women in their early 40s. It’s true that the average age of menopause (a full year without having a period) is age 51, but perimenopause can last for 5-15 years before this time, and it’s marked with small symptoms that can leave women feeling unlike themselves. Though to be clear, you can absolutely still conceive at this time in your life! As long as you are menstruating, you can get pregnant!

The more you know about your estrogen levels and how they change over time, the more prepared you can be to make lifestyle choices that will help you feel your best. That’s where our sister app MBODY comes in.

MBODY is a woman's guide to healthy hormones and a happier, more vibrant life and is for all women who want to understand their hormones and optimize their wellness in their 30s, 40s, and beyond.

Do you have more questions about estrogen, progesterone, or other hormones critical to women’s health? Let us know in the comments below and we’ll do our best to answer them!

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